The Peony Pavilion by the National Ballet of China at this year's Edinburgh international festival. Photograph: Murdo Macleod for the Guardian

The Edinburgh festivals face serious problems putting on large events next year because the London Olympics will lead to a major shortage of technicians and road crew, according to one of the festival fringe's most senior producers.

Anthony Alderson, director of the Pleasance theatre, said on Sunday that the clash with the 2012 games had posed a "real challenge" to next year's festivals because they would soak up all the best lighting, sound and staging technicians in the UK.

The festivals are likely to need to hire staff from Scandinavia, eastern Europe and even Australia, he said, leading to significant extra transport costs and serious problems with the UK's strict visas policy which restricts entry to performing artists.

The director of the Pleasance, one of the fringe's "big four" venues, said producers would need support finding and paying for foreign staff.

"Building an event the size of the Olympics takes a hell of a lot of people. Who's going to come to build the Edinburgh festival next year?" he said.

"It's a real challenge. They are very skilled people and London is going to need a lot of them."

The Olympics will run from 27 July to 14 August, clashing directly with the festivals, which traditionally start around the first or second weekend of August.

This year's fringe, one of up to 10 festivals in the city during July and August, involves 2,542 shows and events. The busiest venues stage up to 48 shows per day.

The organisers of the Glastonbury festival have already decided to drop their annual event next June because of the Olympics and all the associated events surrounding it, which will cause a shortage of police officers and temporary toilets.

Alderson, who also runs the Pleasance theatre in London, said he expected existing technicians to be hired to put up and run a very large number of corporate events, Olympics-related sites and media facilities across the capital.

He also fears Edinburgh will face a similar challenge when Glasgow hosts the Commonwealth games in July 2014. Faith Liddell, director of Festivals Edinburgh, the events' umbrella body, said the issue would be investigated as part of preparations for next year.

Kath Mainland, chief executive of the fringe, said the problem of hiring technicians was under discussion.

The festival was working closely with the venues on these "new challenges", she said, and suggested that Creative Scotland may need to ask for help from abroad.

"The fringe has been having a similar conversation about whether we can bring in qualified technicians, who would have the opportunity to learn from the immense training opportunity of building a venue and then putting on 48 shows in one day in one space," she said.

Alderson said he had already been hiring technicians from Finland this year.